Mergers and Acquisitions

NGC 2207 is a pair of colliding spiral galaxies. Although individual stars are too far apart to collide, the material between them combines to create high-density pockets of gas. Those, in turn, gravitationally collapse, triggering a firestorm of star birth. This galaxy collision will go on for several millions of years, leaving the galaxies’ shapes completely altered.

This animation combines data from three satellite observatories. Optical: Hubble data shows trails of stars and gas trace out spiral arms, stretched by the tidal pull between the galaxies. Infrared: Spitzer data reveals the glow of warm dust; raw material for the creation of new stars and planets. X-ray: Chandra view reveals areas of active star formation and the birth of super star clusters.

Video Credit: STScI

Cassiopeia A

The expanding debris cloud known as Cassiopeia A is an example of the final phase of the stellar life cycle. This false-color image was out together using X-ray and optical image data from the Chandra X-ray Observatory and Hubble Space Telescope. IT shows the still hot filaments and knots in the remnant which span about 30 light-years. High-energy X-ray emission from specific elements have been color coded red for silicon, yellow for sulphur, green for calcium, and purple fr iron. The outer blast wave is shown in blue. The bright speck near the center is a neutron star, the incredibly dense, massive collapsed remains of the star’s core.

Image Credits: NASA /STScI

Messier 2

Messier 2 or M2 (aka NGC 7089) is a globular cluster in the constellation Aquarius. It’s one of the larger globular clusters known—rich, compact, and significantly elliptical—containing over 150,000 stars. It’s one of the oldest globulars in our galaxy, around 13 billion years old. This Hubble image shows the core of the cluster.

Image Credits: NASA, ESA, STScI, and A. Sarajedini (University of Florida)